Apparatus for forming blocks of concrete or other hardening material



,Apnl 9, 1946. F. A. WILLIAMS 2, 7

APPARATUS FOR FORMING BLOCKS OF CONCRETE OR OTHER HARDENING MATERIAL IFiled Oct. 1, 1942 r Patented Apr. 9, 1946 APPARATUS FOR FORMING BLOCKSOF CONCRETE OR OTHER HARDENING MA- TERIAL Francis A. Williams, Toronto,Ontario, Canada, assignor of one-half to New-Era Walls, Limited, andone-half to Cyclops Commercial and Construction Co. Ltd, both ofToronto, Ontario,

Canada Application October 1, 1942, Serial No. 460,462

1 Claim.

This invention relates to the manufacture of blocks of concrete or otherplastic material used in the construction of the walls of buildings orother structures. The material for such building blocks is usually fedinto an individual form or mold, compacted in the mold by (1) tamping or(2) vibrating and, after compacting has been completed, removed from themold in a separate operation.

As the present invention is based on vibrating the material and does notemploy tamping, it is unnecessary to discuss any of the older methods orapparatus in which tamping is employed in the present application.

In existing machines where the compacting is effected by vibration,while the vibration affects the whole system, including the, mold aswell as the cores,,such vibration does not aifect equally all the strataof the material in the moldand the lower part, due to the weight of thematerial above it, is always compacted to a greater extent than theupper portion. In many cases therefore this upper portion has to befurther compacted by other means, usually pressure, which makes theapparatus and its operation more complicated.

Another old and widely used method of compacting concrete in the mold ofa block-making machine or in any form into which the concrete has beenpoured, is that of introducing vibrating bodies, usually of cylindricalform, into the concrete producing an internal vibration of the mass, andwithdrawing the vibrating bodies after a certain time. This principle isused in many cases in producing concrete structures (reinforced orotherwise) both where the material is cast in its permanent location orwhere the material is cast in special machines for use elsewhere. It isobvious that the fact that the vibrating bodies in these cases penetratethe material from one side, mostly from above and leave it later bywithdrawal in the opposite direction has the consequence that thesurface of the concrete or other plastic material which has beeneifected first by the entering vibrator is also the last one to be leftby the withdrawing device and so gets the most amount of A vibration,while the other strata receive less and less vibration, the deeper theyare in the material. The method of vibration used with the presentinvention provides exactly the=same amount of vibration for all of thestrata. This is being attained by an arrangement in which the plasticmaterial passes through a vibrating system in a continuous flow in onedirection. In the vibrating system the position of the cores and moldrelative to each other, remains unchanged ex cept as the result of thevery small amount of vibration mentioned.

5 The principal object of the present invention is to provide a simple,cheap, rapidly and economically operated apparatus by means of whichvarious types of building blocks may be manufactured. In the improvedapparatus the wet mixture of the material is fed into the upper end of abottomless mold and is extruded downwardly incompacted condition fromthe open lower'end of the mold thus providing in effect a continuousprocess by means of which a continuous mass of compacted material of thecross sectional shape of the desired block or structure is extruded fromthe mold for division into sections of the desired height to form theindividual blocks; V The material after being fed into the, mold isimmediately subjected to agitation by means of vibrating cores and/or avibrating mold, which agitation has the three fold object of (1) causingthe material to pass downwardly in the mold, (2)

to compact the material so that the blocks formed from thematerial havethe necessary. densityand strength and (3) to free the new block fromthe mold by counteracting the friction between the walls of the mold andcores against the concrete,

possible. I I

The method of vibrating the cores and/or bottomless mold has thefollowing advantages.

1. Every stratum of material passing down the vibrating core receives anequal amount of vibration. 2. No pressure from above is needed, sincethe particles before leaving the mold bottom have suflicient weight ofconcrete above them to prevent. them from bouncing as they would ifthere is no load upon them, but the agitation of the upper materialcauses it to move downwardly, thus exerting a pressure on the materialbelow it and tending to further compact the latter.

ically free the concrete to be extruded so that no separate operation isneeded to overcomethe friction between concrete and mold. This frictiondue to the tightly compacted state of the concrete is always so great,that thepower required to free the new block from the mold is veryconsiderable with the existing machines.

The object is obtained by means of the constructions hereinafterdescribed and illustrated in as the accompanying drawing in which:

making a downward free extrusion of the block 3. The vibrating moldand/or cores automat- A Fig. 1 is a plan view of the improved apparatus.

Fig. 2 a longitudinal section along the line 22 in Fig. 1. i

Fig. 3 a cross section along the line 33 in Fi 1.

Fig. 4 a plan view of a modified form of knife.

Fig. 5 a side elevation, partly broken away, showing a modifiedarrangement of agitating the cores.

In the drawing, like numerals of reference indicate corresponding partsin the different figures.

l indicates a supporting frame which may be made of any suitable shapeand material to support the various working parts of the apparatus.

Supported in this frame adjacent one end thereof is a form or moldcomprising side members 2 end members 3 the upper portion of which isarranged to receive the wet mixture of which the blocks are formed, andits bottom is open to allow the shaped mass to be extruded therefrom.

While building blocks of concrete or other plastic materials aresometimes made solid as hereinafter referred to, it is usual to provideopenings which have not only the purpose of saving material, but themore important purpose of providing air spaces in the wall to provideinsula tion.

These openings are formed by means of suitable cores arrangedintermediate the front and back of the mold or form. In the constructionshown, three full cores 4, and two half cores 5 are shown.

As set out in the preamble of this specification it is desired toimmediately subject the freshly poured material to vibration to compactthe material to an extent suflicient to give the extruded materialsufficient strength and density required in the finished blocks. Thisvibration, as suggested inthe preamble of the specification may beeffected by vibrating the mold, or the cores, .or both, and in Figs. 1,2 and 3 of the drawing, the mold and cores are all arranged to vibrate.

The method of mounting the mold and core members and eifecting theiragitation may be aranged in various ways. The mold is shown resilientlycushioned in the frame I, and in Figs. 1, 2 and 3, the mold and coresare shown as mounted on two longitudinal bars 6, which bars aresupported in a bearing 1 in one end of the frame I, and a bearing 8 inthe opposite end of the frame. These bearings are formed of a suitableresilient material, such as rubber, so that the bars 6 may be vibrated,which in turn causes the vibration of the mold and cores. Metal springsmay, of course, be substituted for the rubber in the bearings.

These bars are connected together by a rod 13 so that the bars 6 may bevibrated in synchronism, and to cause the agitation or vibration of thebars 6, a short tubular shaft!) is mounted on bearings on the rod I3between the bars 6. On this shaft is mounted a pulley l0, which isdriven by a belt H from a motor l2. This shaft has mounted thereon apair of eccentric weights M, which weights when the shaft 9 is rapidlyrotated set up a vibration of the bars 5 and in turn the cores 5, andthe mold. Due to the bars 6 being resiliently mounted it will be seenthat an effective vibration of the bars 6 and the parts carried thereby,will be obtained. It will be evident that in some cases the cores onlymay be vibrated and the mold remain stationary, while in other cases themold might be vibrated and the cores remain stationary.

The wet material is fed into the upper end of the mold above the top ofthe cores by means of the chute or guide iii. In order that the materialwill not remain on the upper end of the cores, the latter have theirtops specially shaped, one suitable method being to incline or bevel theupper ends as shown in Fig. 3. This arrangement not only facilitates themovement of the material from the core tops but also is carefully chosenso as to avoid any gradual building up of material by arching whichwould tend to prevent downward travel of the material in the mold.

Different materials, different degrees of plasticity of the material anddifferent methods of feeding the material will require appropriatechanges in the shape of the 'core tops, but the principle of a shapedtop remains the same. The bars 6, being comparatively thin, althoughsufiiciently strong for this purpose, offer little resistance to thedownward travel of the material, and any space caused thereby is quicklyfilled in as the material in the mold is agitated by the cores and/ormold.

The agitation or vibration of the mold and/or cores not only compactsthe material but also actually assists the downward movement of thematerial by gravity, thus counteracting any friction between thecompacted material, and the walls of the mold or the cores and thusavoiding the use of any secondary means to extrude the compactedmaterial from the mold. This vibration is also used to regulate thefeeding of fresh material into the mold. It is found that hoppers withsteep feed chute are not feasible, as experiments show that with suchsteep chutes, the material tends to arch above the vibration Zone andtherefore stops feeding. On the other hand it is found that with a feedchute which would not feed due to its lack of suflicient inclination thevibration tends to pull the material from the lower part of the hopperinto the mold to replace the material moving downwardly in the mold. andcausing the material, which was piled up in the upper part of the chute,to slide down to take the place of the material which was carried awayby the vibrator.

The mold and also the cores are preferably of greater depth than thedepth of the finished block so as to provide for greater travel of thematerial during the compacting operation, and further to give thenecessary extra space for the additional material to give the necessaryweight required to prevent any loosening ofthe material in the upperpart of the block length about to be extruded from the mold.

The-shaped material as it emerges from the lower end of the mold restsupon a pallet [6, which pallet rests upon a platform I! movablevertically in the frame i. The platform I! is provided with mechanism(preferably a brake) which controls its descent with the loaded palletl6 thereon. When the platform with the loaded tray has descended to thedesired extent, the downward movement of the material in at least thelower part of the mold where compacting is substantially completed willcease due to being stopped by the knives hereinafter referred to. Thecontrol of the descent of the platform I! with the pallet I6 isparticularly important as such descent regulates the time the movingmaterial is subjected to the vibration and assures that .ordinating therate of feed, the compacting and the rate of extrusion, it will beevident that a substantially continuous operation of the apparatus maybe obtained.

The extruded portion of the mass of compacted material below the mold,the height of which is equal to the height "of the desired block, isthen separated from the material above it in order that the pallet withthe extruded material thereon may be removed. The position'of the lineof separation of course will depend on the height desired for the block,but said line will be located, as indicated in Fig. 3, just above thelower end of the core, and after separation the platform I! is dropped afurther distance as indicated in dotted lines in Fig. 3, to free theupper end of the block from the lower end of the core. j

The separation is effected by a pair of knife members l8. These membersl8, as indicated in- Fig. l are formed as sharp edged plates, havingtheir edges provided with U-shaped notches to receive thecorrespondingly shaped cores 5.

As an alternative, the cutting portions of the knife members l8 may beformed, as indicated in Fig. 4, as a series of sharp prongs l8,

These knife members l8 are operable in guideways in the frame I and areshown with hand grips l9 for manual operation. It will be evident ofcourse that other special means may be provided for advancing andretracting the knives.

It will be noticed in Fig. 1 that the notches in the knife members arevery slightly larger than the cores. This is to provide room for aforward and backward slicing motion of the knives and to prevent thevibrating cores from striking the edges of the knives. The knives, dueto the pressure of the material above them, cannot loosen the upperstratum of the new block as in the case of simple shaping and thepressure material above them, leave the block with a finished uppersurface, thus avoiding the necessity of any additional tamping orpressure which might otherwise be necessary to provide the block with asatisfactory surface.

When the knife members have been operated to sever the block from themass, the platform with the pallet and the block thereon are dropped tofree the block from the lower ends of the cores, and the pallet with theblock thereon are removed, the knife members holding the masstemporarily from descending. A fresh pallet is then placed upontheplatform, which is then quickly raised to position the pallet belowthe knives. The knives are then retracted, and the compacted mass againstarts descending to extrude a fresh block length.

Contrary to all previous methods in which the molds are first filled andthen emptied for refilling, the present process is a continuous one,because a fresh block is being made in the mold even at the same time asa compacted one is being extruded, and the fact that the extrusion isintermittently stopped by the knives, does not stop the continuousoperation of the process as a whole, because the temporary resistance tothe downward trend caused by the knives only helps in the compacting ofthe upper block. It will be noted that the mold is never empty except atthe close of operations.

In some cases it may be desired to give to one or more faces of theblocks, a special pattern or configuration. In this case the mold willbe made slightly larger, and special face platesin a indicated at theleft hand side of the mold in Fig. 3 may be employed. These face plateswill travel downwardly with the mass, and each face plate may remainwith its particular block as long as necessary for the purpose desired.

To insure positive downward travel of the face plates, the lowermost onema be connected to the pallet, and the upper ones to one another. Theconnections between the sections, are arranged to provide a narrow spacebetween the sections, as indicated at 20, to permit-the entrance of theknife. i 1

In such case, in removing the block, the face plate will be disconnectedfrom the face plate above it, and the face plate in the bottom of-themold will be connected with the fresh pallet being positioned to receivethe next block.

This use of travelling face plates enables the making of blocks withrough or patterned faces, which faces the friction in the downwardtravel of the material would otherwise destroy. The face plates may havetheir working surfaces treated in the manner disclosed in a pendingapplication No. 353,820 filed August 23, 1940 for the purpose of givingthe blocks a smooth or glossy surface.

As stated above the method of agitating or vibrating the bars 6 shown inFigs. 1 and 2 is only one of the several ways of accomplishing theresult. In Fig. 5 the cores are shown, secured together by bars 6A andthe central core has positioned thereon and is supported from a verticalcylindrical shell in which is located automatic vibrating device 22which may be operated in any convenient manner.

As stated above any suitable means may be provided for controlling thedescent of the platform I! in Fig. 3 of the drawing, a curved brakingmember 23 is pivoted on the frame and extends through an opening in theplatform IT, to frictionall engage the edge of the latter. This brakingmember 23 is provided with an extension 24 adapted to be operated by thefoot to cause the member 23 to frictionally engage the platform toregulate the rate of its descent. Also pivoted on the frame is a levermember 25 which normally occupies a position in which a stop 26 thereonis in position to engage a downward extension of the platform I1, whilethe severing of a block length is effected. The member 25 may then berocked to disengage the stop 26' from the platform, to allow the latterto descend to engage the substantially horizontally directed part ofsaid lever member 25 to hold the plat form while the severed block withits pallet is removed from the platform. The fresh pallet is then placedon the platform and the latter raised to position to receive a freshblock. The further dropping of the platform tounloading position is ofcourse controlled also by the block.

It will be seen from the above description that a very simple, fastmoving and economical apparatus has been devised for carrying out asubstantiallv continuous process of forming blocks by feeding thematerial into the mold, compacting said material while'in the mold andcausing it to travel there-through vibrating the mold and/or the cores,which form the insulating openings-in the blocks, utilizing the weightof the freshly fed material to assist in the compacting of the lowermaterial and extruding the material after it has been compacted, to thedesired density on to supporting pallets, the downward operation ofwhich pallets regulate the rate of extrusion of the compacted material,the necessary height ofthe ma-' terial above each pallet being dividedfrom the main mass to form a block of the desired size. 7

It has also been pointed out that vibrating the material causes it to beextruded freely and uniformly, overcoming the friction between materialand mold. Properly compacted material binds itself so tightly in a moldthat in other machines strong pressure is required to force the newlyformed block from the mold in a separate operation.

In some cases it may be desired to make solid blocks, in which case thecores 4 and 5 will be omitted, and in this case also, the vibration ofthe material may be effected by means of the mold only as provided forabove.

' It may also be desirable to restrict the vibration of the moldrelative to the core, and this result may be obtained by applyingresilient cushions 21 between the bars 6 and the mold, as indicated inFig. 3.

In the specification and claims, the word.

block is used in a broad sense as including flat slabs, cylinders orother shapes which lend themselves for manufacture by extrusion in themanner set forth'above.

What I claim as my invention is:

In apparatus for molding units of concrete or other plastic hardeningmaterial, the combination of a bottomless mold member; a core member insaid mold; means for feeding material into the upper portion of saidmold, a plurality of surface-affecting inner face members arranged edgeto edge and arranged to slidably engage the inner face of the mold totravel through said mold with the material.

' FRANCIS A. WILLIAMS.

